Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Original articles Annals and Essences of Dentistry
Vol. IX Issue 4 Oct- Dec 2017 1a
10.5368/aedj.2017.9.4.1.1
EFFECT OF DIFFERENT POLISHING SYSTEMS ON THE SURFACE ROUGHNESS OF
NANO-HYBRID COMPOSITES: A PROFILOMETRIC STUDY
1 Sudha K
1 Associate Professor
2 Hanisha Reddy K 2 Assisant Professor
3 Seema Reddy O 3 Tutor
4 Laxmana Rao Ch 4 Post graduate Student
5Leela Naga Pavani T 5 Post graduate Student
6 Sravana Laxmi P
6 Post graduate Student
1-6 Department of Conservative Dentistry and Endodontics, Government Dental College and Hospital, Vijayawada, Andhra
pradesh.
ABSTRACT: Aim: The purpose of this study was to compare the influence of different polishing systems on the surface roughness of nano-hybrid composite resins. Materials and Methods: Fourty samples of acrylic blocks were prepared with cold cure acrylic resin in plastic rings of 1 inch diameter. In each acrylic block, a well of 6mm diameter and 2mm depth was prepared by drilling hole in it using a slow speed micromotor. Tetric N-Ceram™ nano composite is placed in the wells prepared using a plastic instrument and covered with a mylar strip. The samples were then cured for 40s through the mylar strips using LED curing light. 60 samples were divided into 4 groups with 15 samples in each group based on polishing regimen used. Group A - Mylar strip, Group B- PoGo diamond polishers, Group C- prophy brushes and Group D- Super-Snap Rainbow kit. The polished resin composite discs were washed, allowed to dry and kept again in 100% humidity for 24 h before measuring the average surface roughness values (Ra). The surface roughness test was performed using a profilometer and surfaces are seen under scanning electron microscope[SEM]. Statistical analysis: The data were analysed by using one-way ANOVA using SPSS 17.0 software. Results: For all the materials, the smoothest surface was obtained with mylar strip and the roughest with prophy brushes(P< 0.05).Conclusion: Mylar strip produced smoothest surface than other polishing systems. KEYWORDS: Nano hybrid composite; Mylar strip; Surface Roughness; Profilometer;
INTRODUCTION
Increase in the demand for esthetic restorative
materials have led the dentists to adopt nanohydrid
composite restorations in the routine dental
practice.1presence of surface irregulaties caused due to
poor polishing and finishing procedures increases plaque
retention resulting in gingival inflammation, superficial
discoloration and secondary caries.2On the contrary,
smooth, highly polished restorations are shown to be less
susceptible to plaque accumulation and extrinsic
discoloration.1
Furthermore, a smooth surface adds to the patient’s
comfort as a change in surface roughness of 0.3µm can
be detected by the tip of the tongue.3,13
Nanocomposites
provide the aesthetic properties required for anterior
restorations, higher surface quality and superior polish
retention. They also exhibit increased wear resistance, low
shrinkage and also possess favorable mechanical
properties.4Polishing is the process carried out after the
finishing procedure to remove minute scratches from the
surface of a restoration and obtain a smooth, light
reflective luster. The ultimate asthetics of these tooth
coloured restoratives is strongly influenced by the final
surface polish. Smooth highly polished restorations have
been shown to be more easily maintained than restoration
with rougher surface.5
Several studies have demonstrated that flexible
aluminum oxide disks provide the smoothest composite
surface. Unfortunately, the use of these disks is not
always possible because of the anatomic shape and
difficult access to the restoration. Thus, various special
shapes of rubbers and abrasive-impregnated strips are
necessary. Factors that can influence the surface
roughness of composites include the type, size and
quantity of load of the composite as well as the type, size
and hardness of the abrasives and the finishing and
polishing technique used.6
A variety of instruments are commonly used for
finishing and polishing tooth-coloured restorative materials
including: carbide finishing burs, 25-50 µm diamond
Original articles Annals and Essences of Dentistry
Vol. IX Issue 4 Oct- Dec 2017 2a
finishing burs, abrasive impregnated rubber cups and
points, aluminum oxide coated abrasive discs, abrasive
strips, and polishing pastes5,6,7
. A number of finishing and
polishing devices are available, but to decide the efficacy
of various materials is still a challenge to the dentists or
clinicians. Hence, the study was undertaken to determine
the effectiveness of three polishing systems on an
aesthetic material by evaluating surface roughness using
a Profilometer and scanning electron microscope.
Materials and Methods:
Sixty samples of acrylic blocks were prepared with
cold cure acrylic resin in plastic rings of 1 inch diameter. In
each acrylic block, a well of 6mm diameter and 2mm
depth was prepared by drilling hole in it using a slow
speed micromotor.Tetric N-Ceram™ (IvoclarVivadent)
nano composite is placed in the wells prepared using a
plastic instrument and covered with a mylar strip. The
samples were then cured for 40sec through the mylar
strips using LED curing light. Samples were divided into 4
groups with 15 samples in each group based on polishing
regimen used.
Group-I n=15 Control group- Mylar strip
Group-II n=15 PoGo diamond polishers [DENTSPLY]
Group-III n=15 SMART prophybrushes [STODDARD]
Group-VI n=15 Super-Snap Rainbow kit[SHOFU]
Except for the Mylar strip groups, specimens in the
other three subgroups were wet-grounded for 30 s with
1200-grit silicon carbide paper on a metallurgical finishing
wheel to provide a baseline before applying the polishing
systems. The polished resin composite discs were
washed, allowed to dry and kept again in 100% humidity
for 24 h before measuring the average surface roughness
values (Ra). The surface roughness test was performed
using a PROFILOMETER [Taylor Hobson Ltd., Leicester,
England ] and surfaces are examined under scanning
electron microscope(SEM) [ZEISIS, Department of
physics , Osmania university, Hyderabad] . The data were
analyzed by using one-way ANOVA (analysis of variance)
for comparison of the groups [Table 1]
Results:
For all the materials, the smoothest surface was
obtained with mylar strip and the roughest with smart
prophy brushes[STODDARD]. However, Super-Snap
Rainbow kit[SHOFU] created maximum smoothness
among all the polishing systems tested.[Graph 1]
Table 1:- Comparison of surface roughness between the study groups
Mean SD ANOVA
F-value p-value
Group
1 0.154 0.005
3649.65 <0.0001*
Group
2 0.253 0.007
Group
3 0.355 0.006
Group
4 0.172 0.003
n=15 for all the groups; *p < 0.05 statistically
significant; p > 0.05 Non significant, NS Discussion:
Finishing is defined as the gross contouring or
reduction of a restoration to obtain ideal anatomy.
Polishing refers to the reduction of roughness and
scratches created by finishing instruments.10
To increase
the esthetics and longetivity of restoration proper finishing
and polishing of dental restoration is essential. A surface
roughness of 0.7-1.4µm increases plaque accumulation on
the surface of composites. Previous studies had stated
that curing the composite against the mylar strip produced
smoothest surface. But in the clinical scenario that finish
cannot be obtained.8 There are many instruments which
are commonly used for finishing and polishing which
include finishing burs, abrasive rubber cups, aluminium
oxide discs and polishing pastes.5,6,7,9,11,12
. When we cure
with mylar strip some surfaces me exposed which are
resin rich and easily abraded in the oral cavity. If these
surfaces are not properly polished they may retain as
rough surface on which surface plaque may be
inhabitated. The present study employed wet 1200-grit
silicone carbide paper for finishing the resin composite
surface to simulate the clinical scenario.1
After curing the
composite when we remove the excess material with
contouring instrument it is difficult to retain the natural
gloss of that surface. Hence we need proper polishing
agent to get a smoother surface.
In this invitro study prolifilometer is used to measure
the surface roughness. Scanning electron microscope is
used to qualitatively assess the surface roughness.In this
study we use both multiple step and one step polishing
systems namely shofu Super Snap and PoGo
respectively. Super snap rainbow kit are aluminium discs
which causes significant reduction in surface roughness.
In this study Super-Snap kit gave smoother surface
compared to PoGo one step diamond polishers. Although
it is difficult to produce smoother surfaces with aluminium
oxide discs in the posterior regions there ability to cut the
matrix and filler particle equally increased their capability
of producing smoother surfaces than other systems.7,5
Original articles Annals and Essences of Dentistry
Vol. IX Issue 4 Oct- Dec 2017 3a
0.154
0.253
0.355
0.172
0
0.1
0.2
0.3
0.4
GROUP 1 GROUP 2 GROUP 3 GROUP 4
Graph 1: Comparison of Surface Roughness values among Groups
Scanning Electron microscope pictures of the surface surfaceness of different groups under study
Fig. 1. PROPHY BRUSHES[STODDARD]
Fig. 2. PoGo [DENTSPLY]
Fig. 3. MYLAR strip
Fig.4.Super Snap [SHOFU]
Original articles Annals and Essences of Dentistry
Vol. IX Issue 4 Oct- Dec 2017 4a
Though diamonds (PoGo) abrasives gave a good surface
finish, they were found to be rougher than the surface
finish produced by aluminum oxide (Super-snap) discs.7,10
This could be attributed to the fact that diamond (PoGo)
discs are less flexible as compared to the extremely
flexible aluminum oxide discs.5,6,7
This results are in
accordance with the study conducted by watnable et al.8
The highest level of roughness for all composites was
observed after the application of prophy brushes
[STODDARD]. The abrasive potential of prophy brushes
proved to be relatively low and thus, the surface
irregularities following finishing were not sufficiently
removed.
Qualitative Evaluation
Qualitative assessment of the SEM photomicrographs
accorded well with the quantitative results. The surface
roughness increased in the order with Mylar strip being the
finest followed by Super-Snap polishers and the PoGo
discs with the proxy brush creating the highest level of
surface roughness.
The highest level of roughness for all samples was
observed after the application with prophy brushes (Fig.1).
Surfaces after treatment with PoGo discs were mainly
characterized by the remaining minor grooves and surface
irregularities (Fig. 2). Mylar strip group produced minor
roughness and very smooth surface when compared with
all the three polishing syste (Fig.3). Super-Snap polishers
had the greatest smoothing effect and achieved the
largest number of smooth and homogeneous surfaces
among all polishing systems used (Fig. 4).
CONCLUSION:
Within the limitations of the present study, it can be
concluded that mylar strip provided a smoother surface
than Super-Snap discs and PoGo discs. Furthermore,
Super-Snap discs produced smoother surfaces than Po-
Go discs. Super-Snap and PoGo systems produced
clinically acceptable surface roughness for nanohybrid
composites.
References
1. Patel B, Chhabra N, Jain D. Effect of different
polishing systems on the surface roughness of nano-
hybrid composites. J Conserv Dent, 2016;19:37-40.
2. Bashetty K, Joshi S. The effect of one-step and
multi-step polishing systems on surface texture oftwo
different resin composites. J Conserv Dent
2010;13:34-8
3. Jones CS, Billington RW, Pearson GJ. The in vivo
perception of roughness of restorations. Brit Dent
J, 2004;196:42-45.
4. Jung M, Eichelberger K, Klimek J. Surface
geometry of four nanofiller and one hybrid composite
after one-step and multiple-step polishing. Oper
Dent 2007 ; 32(4): 347-355.
5. G S Gulati, R S Hegde. Comparative Evaluation of
two Polishing Systems on the Surface Texture of an
aesthetic material (nano-composite): A Profilometric
Study. People’s Journal of Scientific Research, 2010
;3(2):17-20.
6. Scheibe KG, Almeida KG, Medeiros IS, Costa JF, Alves CM. Effect of different polishing systems on the surface roughness of microhybrid composites. J Appl Oral Sci. 2009;17(1):21-6.
7. Uçtaşli MB, Arisu HD, Omürlü H, Eligüzeloğlu E, Ozcan S, Ergun G. The effect of different finishing and polishing systems on the surface roughness of different composite restorative materials. J Contemp Dent Pract, 2007;8(2):89-96.
8. Nair VS, Sainudeen S, Padmanabhan P,
VijayaShankar LV, Sujathan U, Pillai R. Three-
dimensional evaluation of surface roughness of resin
composites after finishing and polishing. J Conserv
Dent 2016;19:91-5.
9. Media A. Saeed, Intesar S. Toma, Razawa K.
SaeedZanco,The effect of two finishing and polishing
systems on the surface roughness of two composite
resins. J. Med. Sci, 2013;17(3):484-489.
10. Korkmaz Y, Ozel E, Attar N, Aksoy G. The influence
of one-step polishing systems on the surface
roughness and microhardness of nanocomposites.
Oper Dent 2008 Jan-Feb;33(1):44-50
11. Senawongse P, Pongprueksa P. Surface Roughness
of Nanofill and Nanohybrid Resin Composites after
Polishing and Brushing, J Esthet Restor Dent,
2007;19:265–73
12. Sibel A. Antonson a, A. RuyaYazici b, EvrenKilinc c,
Donald E. Antonsona,Patrick C. Hardigan d,
Comparision of different finishing/ polishing systems
on surface roughness and gloss of resin composites,
Journal of dentistry 39 s( 2011 ) e 9- e 17.
13. B S H Itanto, M Usman and A Margono, Comparison
of surface roughness of nanofilled andnanohybrid
composite resins after polishing with a multi-
steptechnique,2017 J. Phys Conf. Ser. 884 012091.
Corresponding Author
Dr.Ch Laxman rao post graduate student,
Department of conservative Dentistry and Endodontics,
Govt. Dental College and Hospital, Vijayawada – 520004, Andhra Pradesh. India.
Email :–[email protected]. Phone No. 8464988464